Deprecated: Function eregi() is deprecated in /home/h101150-2/siemens71.ru/docs/new/cat.php on line 184
General information
The information of the analyzers is collected over the communications network and saved in the central ASM database for further analysis. The ASM is accessed using a Windows workstation, and it is possible to navigate between overview displays, device-specific displays, and general functions.
Overview of analyzers in a plant
The ASM has the following function modules for each analyzer for carrying out the HMI tasks:
|
Module |
Task |
|---|---|
|
Process |
Provides a detailed overview of the selected analyzer. The current analyzer status, planned maintenance work, and configuration data are displayed. The current measured values are displayed in a table, historical values can be analyzed with the trend display using selectable time windows. |
|
Validation |
Checking the reliability of the measured values of analyzers using various routines and methods. This test can be started automatically at specific intervals or manually by the ASM. |
|
Calibration |
Carries out a calibration on the analyzer and monitors the results (this module is only available for analyzers which support remote calibration, e.g. Siemens Maxum Ed. II, Siemens MicroSAM, …). |
|
Maintenance |
Device-specific maintenance tasks can be specified here, their timing defined, and checked. Documentation such as maintenance procedures or manuals can be opened to support the maintenance work. The view of key performance indicators (KPI) provides a fast overview of the analyzer's performance such as availability, error rate and maintenance frequency |
|
Reporting |
This is a comprehensive function for producing customized reports. The module permits analysis of current and historical data in selectable time periods for documentation of the performance of individual analyzers up to the complete plant using the reporting module. The reports can be saved in the ASM or exported for further use. |
View of the maintenance module
Examples of generated reports
Further functions are:
|
Function |
Task |
|---|---|
|
SCADA |
The ASM provides all typical SCADA functions such as: Password protection and different access privileges User administration Signaling, acknowledgment and archiving of alarms and events |
|
Network screen |
Status display of the network devices. This overview displays the statuses of the Ethernet switches (online/uncertain/fault). The analyzer alarms are integrated in the ASM signaling system. |
|
Reference bottle management |
Management and assignment of reference gas cylinders. This information serves as reference values for the validation using the reference sampling method. |
|
Equipment engineering |
For configuring the analyzers. Among others, the analyzer-specific data is entered here, the type of validation is defined, and the number of measured values and units is entered. |
|
Maxum software |
Direct calling of the comprehensive Siemens configuration and operation software for Siemens Maxum edition II and MicroSAM. It is then possible to access the connected analyzers for maintenance, configuration, or viewing of chromatograms. |
Validation
One of the core functions of the ASM is checking the analyzers for reliability of the measured values. Two different methods of measurement are available for recording the values, namely the reference sample method and the line sample method. The resulting values can be checked using different evaluation methods (based on ASTM D3764 or deviation). The objective of the validation is to recognize fluctuations and deviations with respect to a comparison value, and to thus permit a statement to be made on the reliability and drift of the measurement.
Method of measurement: reference sample method
The analyzer is disconnected from the process gas, and a reference gas connected for measurement. The composition of this reference gas has previously been specified in the "Reference bottle management" of the ASM. Using these values, the ASM determines the deviation between the measurement and the reference data.
Method of measurement: line sample method
With this method, a gas sample is extracted from the stream of sample gas to the analyzer, and analyzed in the laboratory. The resulting values are passed on to the ASM and compared with the analyzer's measured values. With this method, the analyzer need not be disconnected from the process gas, and permanently remains available for the process measurement.
Evaluation based on ASTM D3764
Based on the international standard ASTM D3764, the results are checked using various statistical methods, including standard deviation, Dixon freak value test, and systematic error.
Evaluation using deviation method
Limit values are defined for this evaluation: the warning limit and the control limit. Simple rules are used to define how the reliability of the measurement is to be assessed when these limits are violated. For example, it can be defined that a single violation of the limit can be tolerated, but that repeated violation is an impermissible condition.
View of the validation module